1. Field of the Invention
The invention resides in the field of medical technology and concerns a device and a method for dispensing a material in a human or animal patient. Device and method serve for dispensing a material with thermoplastic properties in a flowable state, i.e. for bringing the material with thermoplastic properties from a solid state into a flowable state and depositing the material in the flowable state at a desired site to re-solidify. Device and method are specifically adapted for dispensing relatively small amounts of the material at an operation site in a human or animal patient but may of course also be used for dispensing the material at any other site. The device, preferably being a hand-held device, either contains the material with thermoplastic properties or is chargeable with it. The material is made flowable in a distal end portion of the device, while this distal end portion is positioned at the site where dispensing is desired.
2. Description of Related Art
Surgical processes in which materials with thermoplastic properties are liquefied in situ, are known e.g. from the publications U.S. Pat. No. 7,335,205, U.S. Pat. No. 7,008,226, WO-2005/079696, or WO-2008/034277. These publications disclose in particular methods for anchoring an implant in tissue with the aid of a material, which has thermoplastic properties and is comprised by the implant, and with the aid of vibration energy, in particular ultrasonic vibration energy. Therein the implant or part thereof is pressed against the tissue or against another implant part whereby the thermoplastic material constituting a surface of the implant or implant part is liquefied and made to penetrate the tissue where, on re-solidification, it constitutes a positive fit connection between the tissue and a portion of the thermoplastic material which was not liquefied.
The publication U.S. Pat. No. 6,620,185 discloses a device for anchoring a suture in an opening in bone tissue, wherein a material with thermoplastic properties is brought into the opening in a flowable state. The material with thermoplastic properties is stored in the dispensing device in a solid state (pellets or flexible rod to be handled like the suture), is driven to a distal device end through a cannula by pressurized air and for being dispensed is melted at this distal end, which for the melting process comprises an electric heating element, or means for inductive heating or heating with ultrasound or laser light.